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>Chapter 44. Overview of PostgreSQL Internals</H1
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><B
>Table of Contents</B
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>44.1. <A
HREF="query-path.html"
>The Path of a Query</A
></DT
><DT
>44.2. <A
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>How Connections are Established</A
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><DT
>44.3. <A
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>The Parser Stage</A
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>44.3.1. <A
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>Parser</A
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>44.3.2. <A
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>Transformation Process</A
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>44.4. <A
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>The <SPAN
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>PostgreSQL</SPAN
> Rule System</A
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>44.5. <A
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>Planner/Optimizer</A
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>44.6. <A
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>Executor</A
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>Author: </B
>    This chapter originated as part of
    <A
HREF="biblio.html#SIM98"
><I
>Enhancement of the ANSI SQL Implementation of PostgreSQL</I
></A
>, Stefan Simkovics'
    Master's Thesis prepared at Vienna University of Technology under the direction
    of O.Univ.Prof.Dr. Georg Gottlob and Univ.Ass. Mag. Katrin Seyr.
   </P
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>   This chapter gives an overview of the internal structure of the
   backend of <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
>.  After having
   read the following sections you should have an idea of how a query
   is processed. This chapter does not aim to provide a detailed
   description of the internal operation of
   <SPAN
CLASS="PRODUCTNAME"
>PostgreSQL</SPAN
>, as such a document would be
   very extensive. Rather, this chapter is intended to help the reader
   understand the general sequence of operations that occur within the
   backend from the point at which a query is received, to the point
   at which the results are returned to the client.
  </P
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